Overlapping printed circuit boards and electronic device including same

ABSTRACT

According to an embodiment of the disclosure, an electronic device comprises a first printed circuit board including a first electrical terminal exposed on one face of a first area, a second electrical terminal exposed on the one face of a second area and insulated from the first electrical terminal, and a first ground terminal exposed on the one face of a third area formed between the first area and the second area, the third area having a width narrower than a width of the first area or the width of the second area; and a second printed circuit board including a third electrical terminal exposed on one face of a fourth area, a fourth electrical terminal exposed on the one face of a fifth area and electrically connected to the third electrical terminal, and a second ground terminal exposed on the one face of a sixth area located between the fourth area and the fifth area, wherein the second printed circuit board is disposed on the first printed circuit board to overlap the third area, the first electrical terminal and the third electrical terminal are electrically coupled to each other, the second electrical terminal and the fourth electrical terminal are electrically coupled to each other, and the first ground terminal and the second ground terminal are electrically coupled to each other.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation application of prior application Ser.No. 16/413,797, filed on May 16, 2019, which is based on and claimspriority under 35 U.S.C. § 119(a) of a Korean patent application Serialnumber 10-2018-0061270, filed on May 29, 2018, in the KoreanIntellectual Property Office, the disclosure of which is incorporated byreference herein in its entirety.

BACKGROUND 1. Field

Certain embodiments relate to overlapping printed circuit boards and anelectronic device including the printed circuit boards.

2. Description of Related Art

The above information is presented as background information only toassist with an understanding of the disclosure. No determination hasbeen made, and no assertion is made, as to whether any of the abovemight be applicable as prior art with regard to the disclosure.

With the development of digital technologies, electronic devices arebeing produced in various forms such as a smart phone, a tablet personalcomputer (PC), and a personal digital assistant (PDA). Electronicdevices are also being developed in a user wearable form in order toimprove portability and a user's accessibility. An electronic device mayinclude a printed circuit board connecting electronic components, andthe printed circuit board may support data input/output and dataexchange between the electronic components.

SUMMARY

A printed circuit board may include, for example, an area having that isrelatively thin, which may be more likely than other areas to be damaged(cracked) due to an impact when the printed circuit board is coupled toor separated from an electronic device. The thickness of the area may beincreased to make the area more rigid. However, this may consume more ofthe internal space in the electronic device and make it difficult toinstall other elements.

Electronic components may transmit or receive data signals throughsignal lines etched on the printed circuit board. Due to current flow,an electric field is formed in the signal lines, and this electric fieldcauses electromagnetic interference (EMI) that interferes with thenormal operation of the electronic components by introducing noise to anearby electronic component or signals transmitted to another nearbysignal line. In order to suppress such electromagnetic interference(e.g., noise), the signal lines may be designed to be located as far aspossible from the nearest signal lines and electronic components, or maybe designed such that the signal strength is high. However, withportable electronic devices large numbers of electronic components forvarious functions and signal lines associated therewith are being addedto relatively small-volume electronic devices. In this regard, it isbecoming more difficult to design the signal lines in a printed circuitboard (e.g., the area formed in a relatively narrow width in the printedcircuit board).

An embodiment of the disclosure provides overlapping printed circuitboards disposed to reinforce the rigidity of at least a portion of theprinted circuit boards and an electronic device including the printedcircuit boards.

An embodiment of the disclosure provides overlapping printed circuitboards disposed to secure a wiring area and an electronic deviceincluding the printed circuit boards.

According to an embodiment of the disclosure, an electronic devicecomprises a first printed circuit board including a first electricalterminal exposed on one face of a first area, a second electricalterminal exposed on the one face of a second area and insulated from thefirst electrical terminal, and a first ground terminal exposed on theone face of a third area formed between the first area and the secondarea, the third area having a width narrower than a width of the firstarea or the width of the second area; and a second printed circuit boardincluding a third electrical terminal exposed on one face of a fourtharea, a fourth electrical terminal exposed on the one face of a fiftharea and electrically connected to the third electrical terminal, and asecond ground terminal exposed on the one face of a sixth area locatedbetween the fourth area and the fifth area, wherein the second printedcircuit board is disposed on the first printed circuit board to overlapthe third area, the first electrical terminal and the third electricalterminal are electrically coupled to each other, the second electricalterminal and the fourth electrical terminal are electrically coupled toeach other, and the first ground terminal and the second ground terminalare electrically coupled to each other.

According to certain embodiments, it is easy to reinforce at least someareas of the first printed circuit board and to secure a wiring areausing one or more second printed circuit boards that overlap and coupledto the first printed circuit board, without increasing the wiringdensity in the areas or without designing the areas so as to expand thewidth thereof.

In addition, effects obtainable or predicted by certain embodiments ofthe disclosure will be directly or implicitly disclosed in the detaileddescription of the embodiments of the disclosure. For example, variouseffects that are expected according to certain embodiments of thedisclosure will be disclosed within the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainembodiments of the disclosure will be more apparent from the followingdescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a front side perspective view of a mobile electronic deviceaccording to an embodiment;

FIG. 2 is a rear side perspective view of the electronic device of FIG.1;

FIG. 3 is an exploded perspective view of the electronic device of FIG.1;

FIG. 4A is a view related to a manufacturing flow of a second printedcircuit board in FIG. 3;

FIG. 4B is a view related to a manufacturing flow of a second printedcircuit board in FIG. 3;

FIG. 4C is a view related to a manufacturing flow of a second printedcircuit board in FIG. 3;

FIG. 4D is a view related to a manufacturing flow of a second printedcircuit board in FIG. 3;

FIG. 5A is a view related to a manufacturing flow of a second printedcircuit board in FIG. 3;

FIG. 5B is a view related to a manufacturing flow of a second printedcircuit board in FIG. 3;

FIG. 5C is a view related to a manufacturing flow of a second printedcircuit board in FIG. 3;

FIG. 5D is a view related to a manufacturing flow of a second printedcircuit board in FIG. 3;

FIG. 5E is a view related to a manufacturing flow of a second printedcircuit board in FIG. 3;

FIG. 5F is a view related to a manufacturing flow of a second printedcircuit board in FIG. 3;

FIG. 6 is a view for explaining contouring of a printed circuit boardaccording to certain embodiments;

FIG. 7 is an exploded perspective view of printed circuit boardsaccording to an embodiment;

FIG. 8 is a cross-sectional view of a printed circuit board according toan embodiment;

FIG. 9 is a view illustrating an electronic device includingoverlappingly disposed printed circuit boards according to certainembodiments;

FIG. 10 is a view illustrating an electronic device includingoverlapping printed circuit boards according to certain embodiments;

FIG. 11A is a front view of a second printed circuit board according tocertain embodiments;

FIG. 11B is a rear view of the second printed circuit board of FIG. 11A;

FIG. 12 is a view illustrating a second printed circuit board accordingto certain embodiments;

FIG. 13 is a view illustrating a printed circuit board according tocertain embodiments; and

FIG. 14 is a block diagram of an electronic device, includingoverlapping printed circuit boards, within a network environmentaccording to certain embodiments.

DETAILED DESCRIPTION

Hereinafter, certain embodiments of the disclosure will be describedwith reference to the accompanying drawings. The certain embodiments andthe terms used herein are not intended to limit the technical featuresdisclosed herein to specific embodiments, and should be understood toinclude various modifications, equivalents, and/or alternatives to thecorresponding embodiments. In describing the drawings, similar referencenumerals may be used to designate similar constituent elements. Thesingular form of a noun corresponding to an item may include one item ora plurality of items unless the relevant context clearly indicatesotherwise. In the disclosure, the expression “A or B”, “at least one ofA and B”, “at least one of A or B”, “A, B, or C”, or “at least one of A,B, or C” may include all possible combinations of items enumeratedtogether. The expression “a first”, “a second”, “the first”, or “thesecond” may modify corresponding elements regardless of the order orimportance, and is used only to distinguish one element from anotherelement, but does not limit the corresponding elements. When an element(e.g., first element) is referred to as being “coupled” or “connected”to another element (second element) with or without the term“functionally” or “communicatively”, the element may be connecteddirectly (e.g., wiredly) to the another element or connected to theanother element through yet another element (e.g., third element).

The electronic device according to certain embodiments disclosed hereinmay be various types of devices. The electronic device may, for example,include at least one of a portable communication device (e.g.,smartphone) a computer device, a portable multimedia device, a portablemedical device, a camera, a wearable device, and a home appliance. Theelectronic device according to one embodiment of the disclosure is notlimited to the above described devices. In the disclosure, the term“user” may indicate a person using an electronic device or a device(e.g., an artificial intelligence electronic device) using an electronicdevice.

FIG. 1 is a front side perspective view of a mobile electronic deviceaccording to an embodiment. FIG. 2 is a rear side perspective view ofthe electronic device of FIG. 1. FIG. 3 is an exploded perspective viewof the electronic device of FIG. 1.

Referring to FIGS. 1 and 2, an electronic device 100 according to anembodiment may include a housing 110 including a first face (or a frontface) 110A, a second face (or a rear face) 110B, and a side face 110Csurrounding a space between the first face 110A and the second face110B. In another embodiment (not illustrated), the term “housing” mayrefer to a structure forming some of the first face 110A, the secondface 110B, and the side face 110C of FIG. 1. According to an embodiment,at least part of the first face 110A may be formed of a substantiallytransparent front plate 102 (e.g., a glass plate or a polymer plateincluding various coating layers). The second face 110B may be formed ofa substantially opaque rear plate 111. The rear plate 111 may be formedof, for example, coated or colored glass, ceramic, a polymer, or a metal(e.g., aluminum, stainless steel (STS), or magnesium), or a combinationof two or more of these materials. The side face 110C may be formed by aside bezel structure (or a “side member”) 118 coupled to the front plate102 and the rear plate 111 and including a metal and/or a polymer. Insome embodiments, the rear plate 111 and the side bezel structure 118may be integrally formed, and may include the same material (e.g., ametal material such as aluminum).

In the illustrated embodiment, the front plate 102 may include two firstareas 110D, which are bent from the first face 110A toward the rearplate 111 and extend seamlessly, at the long opposite side edgesthereof. In the illustrated embodiment (see FIG. 2), the rear plate 111may include two second areas 110E, which are bent from the second face110B toward the front plate 102 and extend seamlessly, at the longopposite side edges thereof. In some embodiments, the front plate 102(or the rear plate 111) may include only one of the first areas 110D (orthe second areas 110E). In another embodiment, some of the first areas110D and the second areas 110E may not be included. In the aboveembodiments, when viewed from a side of the electronic device 100, theside bezel structure 118 may have a first thickness (or width) on theside in which the first areas 110D or the second areas 110E are notincluded, and may have a second thickness (or width), which is thinnerthan the first thickness, on the side in which the first areas 110D orthe second areas 110E are included.

According to an embodiment, the electronic device 100 may include one ormore of a display 101, audio modules 103, 107, and 114, sensor modules104, and 119, camera modules 105, 112, and 113, key input devices 115,116, and 117, an indicator 106, and connector holes 108 and 109. In someembodiments, in the electronic device 100, at least one of thecomponents ((e.g., the key input devices 115, 116, and 117 or theindicator 116) may be omitted, or other components may be additionallyincluded.

The display 101 may be exposed through, for example, a large portion ofthe front plate 102. In some embodiments, at least a part of the display101 may be exposed through the front plate 102 forming the first face110A and the first areas 110D of the side faces 110C. The display 101may be coupled to or disposed adjacent to a touch-sensing circuit, apressure sensor capable of measuring touch intensity (pressure), and/ora digitizer that detects a magnetic-field-type stylus pen. In someembodiments, at least some of the sensor modules 104 and 119 and/or atleast some of the key input devices 115, 116, and 117 may be disposed inthe first areas 110D and/or the second areas 110E.

According to an embodiment, the audio modules 103, 107, and 114 mayinclude a microphone hole 103 and speaker holes 107 and 114. Themicrophone hole 103 may include a microphone disposed therein so as toacquire external sound, and in some embodiments, the microphone hole 125may include multiple microphones disposed therein so as to sense thedirection of sound. The speaker holes 107 and 114 may include anexternal speaker hole 107 and a phone call receiver hole 114. In someembodiments, the speaker holes 107 and 114 and the microphone hole 103may be implemented as a single hole, or a speaker (e.g., a piezospeaker) may be included without the speaker holes 107 and 114.

According to an embodiment, the sensor modules 104 and 119 may generatean electrical signal or a data value corresponding to the internaloperating state of the electronic device 100 or an externalenvironmental condition. The sensor modules 104 and 119 may include, forexample, a first sensor module 104 (e.g., a proximity sensor) and/or asecond sensor module (not illustrated) (e.g., a fingerprint sensor)disposed on the first face 110A of the housing 110, and/or a thirdsensor module 119 (e.g., an HRM sensor) disposed on the second face 110Bof the housing 110. The fingerprint sensor may be disposed not only onthe first face 110A of the housing 110 (e.g., the home button 115), butalso on the second face 110B thereof. The electronic device 100 mayfurther include at least one of sensors (not illustrated) such as agesture sensor, a gyro sensor, an air pressure sensor, a magneticsensor, an acceleration sensor, a grip sensor, a color sensor, aninfrared (IR) sensor, a biometric sensor, a temperature sensor, ahumidity sensor, and an illuminance sensor.

According to an embodiment, the camera modules 105, 112, and 113 mayinclude a first camera device 105 disposed on the first face 110A of theelectronic device 100 and a second camera device 112 and/or a flash 113disposed on the second face 110B. The camera devices 105 and 112 mayinclude one or more lenses, an image sensor, and/or an image signalprocessor. The flash 113 may include, for example, a light-emittingdiode or a xenon lamp. In some embodiments, two or more lenses (e.g., aninfrared camera lens, a wide-angle lens, and a telephoto lens) and imagesensors may be disposed on one face of the electronic device 100.

According to an embodiment, the key input devices 115, 116, and 117 mayinclude a home key button 115 disposed on the first face 110A of thehousing 110, a touch pad 116 disposed in the vicinity of the home keybutton 115, and/or a side key button 117 disposed on the side face 110 cof the housing 110. In another embodiment, the electronic device 100 maynot include some or all of the above-mentioned key input devices 115,116, and 117, and a key input device 115, 116, or 117, which is notincluded, may be implemented in another form such as a soft key on thedisplay 101.

The indicator 106 may be disposed on, for example, the first face 110Aof the housing 110. The indicator 106 may include an LED as long as itcan provide, for example, the state information of the electronic device100 in an optical form.

According to an embodiment, the connector holes 108 and 109 may includea first connector hole 108 capable of accommodating a connector (e.g., aUSB connector) for transmitting and receiving power and/or data to andfrom an external electronic device, and/or a second connector hole 109capable of accommodating a connector (e.g., an earphone jack) fortransmitting and receiving an audio signal to and from an electronicdevice.

Referring to FIG. 3, the electronic device 300 may include a side bezelstructure 310, a first support member 311 (e.g., a bracket), a frontplate 320, a display 330, a printed circuit board(s) (PCB(s)) 340, abattery 350, a second support member 360 (e.g., a rear case), an antenna370, and a rear plate 380. In some embodiments, in the electronic device300, at least one of the components (e.g., the first support member 311or the second support member 360) may be omitted, or other componentsmay be additionally included. At least one of the components of theelectronic device 300 may be the same as or similar to at least one ofthe components of the electronic device 100 of FIG. 1 or 2, and aredundant description is omitted below.

According to an embodiment, the first support member 311 may be disposedinside the electronic device 300 and may be connected to the side bezelstructure 310, or may be formed integrally with the side bezel structure310. The first support member 311 may be formed of, for example, a metalmaterial and/or a non-metal (e.g., polymer) material. The display 330may be coupled to one side of the first support member 311, and theprinted circuit board(s) 340 may be coupled to the other side of thefirst support member 311. On the printed circuit board(s) 340, aprocessor, a memory, and/or an interface may be mounted. The processormay include one or more of, for example, a central processing unit, anapplication processor, a graphic processor, an image signal processor, asensor hub processor, or a communication processor.

The memory may include, for example, volatile memory or nonvolatilememory.

The interface may include, for example, a high definition multimediainterface (HDMI), a universal serial bus (USB) interface, an SD cardinterface, and/or an audio interface. The interface may electrically orphysically connect, for example, the electronic device 300 to anexternal electronic device, and may include a USB connector, an SDcard/an MMC connector, or an audio connector.

The battery 350 is a device for supplying power to at least onecomponent of the electronic device 300, and may include, for example, anon-rechargeable primary battery, a rechargeable secondary battery, or afuel cell. At least a part of the battery 350 may be disposed to besubstantially flush with, for example, the printed circuit board(s) 340.The battery 350 may be integrally disposed within the electronic device300, or may be mounted so as to be detachable from the electronic device300.

The second support member 360 may be coupled to, for example, the firstsupport member 311, and may be disposed between the printed circuitboard(s) 340 and the first rear plate 380. The second support member 360may be coupled to the first support member 311 together with the printedcircuit board(s) 340 using bolt fastening or the like, and may serve tocover and protect the printed circuit board(s) 340.

According to an embodiment, the antenna 370 may be disposed between therear plate 380 and the display 350. The antenna 370 may include, forexample, a near-field communication (NFC) antenna, a wireless chargingantenna, and/or a magnetic secure transmission (MST) antenna. Theantenna 370 is capable of, for example, performing short-rangecommunication with an external device or transmitting and receivingpower required for charging in a wireless manner. In another embodiment,an antenna structure may be formed by the side bezel structure 310, aportion of the first support member 311, or a combination thereof.

According to an embodiment, the printed circuit board(s) 340 may includea first printed circuit board 341 and at least one second printedcircuit board 342 disposed to overlap the first printed circuit board341.

According to an embodiment, the first printed circuit board 341 or thesecond printed circuit board 342 may be a multilayer printed circuitboard. The multilayer printed circuit board may be formed by forming aplurality of inner layers in which a circuit is formed using acopper-clad laminate (CCL) (or an original plate) and laminating theplurality of inner layers. According to some embodiments, the firstprinted circuit board 341 or the second printed circuit board 342 formedon the basis of the copper-clad laminate may be a single-side printedcircuit board in which a circuit is formed on only one side and adouble-sided printed circuit board in which circuits are formed on bothsides.

The second printed circuit board 342 may reinforce, for example, thefirst printed circuit board 341. According to an embodiment, the firstprinted circuit board 341 may include a first area 341A, a second area341B, and a third area 341C disposed between the first area 341A and thesecond area 341B. The third area 341C may be disposed along the side ofthe battery. As a result, the third area 341C may have a narrower widththan the first area 341A or the second area 341B, and may be more likelythan the first area 341A of the second 341B area to be damaged due tocracks or the like (it is noted that the third area 341C may have anarrow width for other reasons). The second printed circuit board 342may be disposed to overlap the third area 341C so as to be used as areinforcing member (e.g., a reinforcing plate) to reinforce the rigidityof the third area 341C. According to certain embodiments, the secondprinted circuit board 342 may be coupled to overlap various other areasof the first printed circuit board 341 that require reinforcement.

The second printed circuit board 342 may provide an electric pathconnected to, for example, the first printed circuit board 341. Forexample, the first printed circuit board 341 may include a first area341A, a second area 341B, and a third area 341C disposed between thefirst area 341A and the second area 341B, and may include a firstelectrical terminal exposed on one face of the first area 341A, and asecond electrical terminal exposed on one face of the second area 341Band physically separated from the first electrical terminal. The secondprinted circuit board 342 may include a third electrical terminalexposed on one face of a fourth area and a fourth electrical terminalexposed on one face of a fifth area, and the third electrical terminaland the fourth electrical terminal are electrically connected to eachother. When the first printed circuit board 341 and the second printedcircuit board 342 are coupled to each other, the first electricalterminal is coupled to the third electrical terminal via solder, and thesecond electrical terminal is coupled to the fourth electrical terminalvia solder. Thereby, the first electrical terminal and the secondelectrical terminal may be electrically connected to each other throughthe second printed circuit board 342. The electrical terminals mayinclude signal terminals, conductive terminals, contact terminals, orconductive pads.

For example, the first printed circuit board 341 may include a firstground terminal exposed at least in some areas (e.g., the third areadisposed between the first area 341A and the second area 341B). Thefirst ground terminal may be a part of a first ground included in thefirst printed circuit board 341 or may be electrically connected to thefirst ground. The second printed circuit board 342 may include a secondground terminal exposed on one face thereof, and the second groundterminal may be a part of the second ground (or a second ground circuit)included in the second printed circuit board 342, or may be electricallyconnected to the second ground. When the second printed circuit board342 is coupled to the first printed circuit board 341, solderinterconnecting the first ground terminal and the second ground terminalis disposed, by which the first ground and the second ground can beelectrically connected to each other. The first ground and the secondground may be utilized as the ground of the corresponding potential, sothat the noise or electromagnetic interference (EMI) generated in theelectronic device 300 can be reduced.

According to certain embodiments, the second printed circuit board 342may include a third ground that is physically separated from the firstground of the first printed circuit board 341. The first ground may havea first potential, and the third ground may have a second potentialdifferent from the first potential. The noise generated in theelectronic device 300 may be attenuated by being dispersed to the firstground and the third ground. For example, a relatively high noise floor(e.g., a measured value for the sum of noise) of the noise generated bythe electronic device 300 may be attenuated either by the first groundor by the third ground.

According to certain embodiments, the second printed circuit board 342may be utilized as a part (e.g., an antenna) of a transmission circuitfor wireless communication. At least a part of the circuit formed on thesecond printed circuit board 342 is electrically connected to acommunication circuit mounted on the first printed circuit board 341,and the communication circuit may support various types of communicationusing the second printed circuit board 343. For example, thecommunication circuit may be electrically connected to the circuit andto a processor (not shown) included in the second printed circuit board342. The communication circuit may include radio frequency (RF)components such as a radio frequency integrated circuit (RFIC) and afront-end module (FEM) between the second printed circuit board 342 andthe processor. For example, the RFIC may receive external radio wavesthrough the second printed circuit board 342, and may modulate thereceived high-frequency waves to a low frequency band (e.g., a baseband)that can be processed by the processor. The RFIC is capable ofmodulating low-frequency waves to high-frequency waves for transmissionin the processor. The FEM may connect the second printed circuit board342 and the RFIC, and may separate transmitted and received signals. Forexample, the FEM may perform filtering and amplification, and mayinclude a reception-end FEM in which a filter is embedded in order tofilter a received signal and a transmission-end FEM in which a poweramplifier module (PAM) is embedded in order to amplify a transmittedsignal.

According to certain embodiments, the second printed circuit board 342may be used for at least one communication system among single inputmultiple output (SIMO), multiple input single output (MISO), diversity,and multiple input multiple output (MIMO).

According to some embodiments, the second printed circuit board 342 maybe utilized as an antenna-matching circuit. The radiationcharacteristics and impedance of an antenna (e.g., the antenna 370 inFIG. 3) are related to antenna performance, and may vary depending onthe shape, size, and material of the antenna. The radiationcharacteristics of the antenna may include an antenna radiation pattern(or an antenna pattern), which is a directional function indicating therelative distribution of power radiated from the antenna, and thepolarization state of electromagnetic waves radiated from the antenna(e.g., antenna polarization). The impedance of the antenna may berelated to the transmission of power from a transmitter to the antennaor from the antenna to a receiver. In order to minimize reflection at atransmission line and an antenna connection portion, the impedance ofthe antenna is designed to match the impedance of the transmission line,thereby enabling maximum power transmission (or minimization of powerloss) or efficient signal transmission through the antenna. Theimpedance matching may induce efficient signal flow at a specificfrequency (or a resonant frequency). Impedance mismatch may cause powerloss or reduce the strength of transmitted/received signals, therebydegrading communication performance. According to an embodiment, thecircuit included in the second printed circuit board 342 may be utilizedas a frequency adjustment circuit in order to eliminate such impedancemismatch.

According to an embodiment, the frequency adjustment circuit may includea switching circuit that switches to at least one designated matchingcircuit (e.g., a circuit included in the second printed circuit board342) or a circuit that adjusts impedance using the second printedcircuit board 342. For example, the frequency adjustment circuit mayshift the resonant frequency to a designated frequency using the secondprinted circuit board 342, or may shift the resonant frequency asspecified.

FIG. 4A-5F are views related to a manufacturing flow of a second printedcircuit board, such as second printed circuit board 342 in FIG. 3.

Referring to FIG. 4A, in an embodiment, a copper-clad laminate (or anoriginal plate) 410 may be formed. The copper-clad laminate 410 is alaminate for use in a printed circuit, and may include a structure inwhich copper foils 412 and 413 are attached to both sides of aninsulating layer (or an insulating plate) 411 composed of various basicinsulating materials (e.g., a resin) and a binder.

The copper foils 412 and 413 may be, for example, electrolytic copperfoils formed through a chemical-electrolytic reaction. According to anembodiment, in order to increase the adhesion with the resin of theinsulating layer 411, the copper foils 412 and 413 may be made tochemically react with the resin to partially (about 5 μm (micrometers))penetrate into the resin when forming the copper foils 412 and 413. Thethickness of an electrolytic copper foil may be about 18 to 70 μm, butthe copper foils 412 and 413 may be variously formed to have thicknessesof 5 μm, 7 μm, and 15 μm, which are thinner than the above-mentionedrange, depending on wiring density or fineness. According to someembodiments, the copper foils 412 and 413 may be rolled copper foilsthat have been rolled and thinned. The thickness of the copper foils 412and 413 may be variously determined depending on the current allowed inthe pattern.

The insulating layer 411 of the copper-clad laminate 410 may include aresin such as phenol or epoxy. The copper-clad laminate 410 may furtherinclude a reinforcing base material (not illustrated) such as paper,glass fiber, or glass non-woven fabric. The reinforcing base material isable to increase rigidity of the insulating layer 411 (e.g.,longitudinal and transversal rigidity), which may be insufficient whenusing only a resin, or to reduce the dimensional change rate of theinsulating layer with respect to temperature.

The copper-clad laminate 410 may be, for example, a glass-epoxycopper-clad laminate including a base material in which a glass fiber isimpregnated (or infiltrated) with an epoxy resin and copper foils 412and 413 bonded thereto. According to an embodiment, the NationalElectrical Manufacturers Association (NEMA) classifies copper-cladlaminates into classes of, for example, FR (flame retardant)-1, FR-2,FR-3, FR-5, and FR-6, on the basis of base materials and flameresistance (flame retardancy), and the glass-epoxy copper-clad laminatemay be one of FR-4 and FR-5. According to an embodiment, FR-4 or FR-5may include a base material in which woven glass fiber impregnated withan epoxy resin are stacked in several layers and copper foils bondedthereto.

The copper-clad laminate 410 may be a paper-phenol copper-clad laminateincluding, for example, a base material in which paper is impregnatedwith phenol resin and copper foils 412 and 413 bonded thereto. Accordingto an embodiment, the paper-phenol copper-clad laminate may be one ofFR-1, FR-2 and FR-3 as classified by the NEMA.

The copper-clad laminate 410 may be, for example, a compositecopper-clad laminate formed by combining two or more reinforcing basematerials. According to an embodiment, the composite copper-cladlaminate may include CEM (composite type of laminate material bondedwith a flame-retardant epoxy resin)-1, CEM-3, or the like as defined bythe NEMA. CEM-1 may include a center base material (or a core) made ofpaper impregnated with an epoxy resin, outer base materials made ofwoven glass fiber impregnated with an epoxy resin, and copper foilsbonded to the outer base materials. CEM-3 may include a core basematerial made of non-woven glass fiber (e.g., glass non-woven fabric)impregnated with an epoxy resin, outer base materials made of wovenglass fiber impregnated with an epoxy resin, and copper foils bonded tothe outer base materials. Glass fiber or paper is capable of improvingmechanical workability, heat resistance, or dimensional stability.According to some embodiments, the copper-clad laminate may be FR-6,which includes a central base material made of non-woven glass fiber(e.g., glass non-woven fabric) impregnated with a polyester resin, outerbase materials made of glass fiber impregnated with a resin, and copperfoils bonded to the outer base materials.

According to certain embodiments, CEM-3 may be designed to replace FR-4or FR-5. CEM-3 has relatively less glass fiber than FR-4 or FR-5, andthus the mechanical strength of CEM-3 may be relatively low. When CEM-3is designed to replace FR-4 or FR-5, the mechanical strength may beconsidered. According to certain embodiments, when punching is required,CEM-3, which is more advantageous for punching, may be applied to themanufacture of printed circuit boards in place of FR-4.

According to certain embodiments, the copper-clad laminate 410 may be ahigh-frequency copper-clad laminate made of a material capable ofwithstanding high-speed signal transmission. For example, in a printedcircuit board, a signal propagation speed is inversely proportional tothe permittivity of a material, and thus it is possible to increase thesignal propagation speed when a material with low permittivity is used.

According to some embodiments, the copper-clad laminate 410 may be inthe form in which a film prepreg made of an insulating material isdisposed on a plate formed of a metal such as aluminum or iron and thena copper foil is bonded to the film prepreg.

According to some embodiments, the copper-clad laminate 410 may includea flexible copper-clad laminate for use in a flexible printed circuitboard (FPCB), or the like. The flexible copper-clad laminate may be, forexample, in the form in which a flexible polyester film or polyimidefilm and a copper foil are bonded to each other with an adhesive.

According to certain embodiments, the copper clad laminate 410 may beformed in a structure including an insulating layer 411 of various othermaterials or structures.

The second printed circuit board (e.g., the second printed circuit board342 in FIG. 3) may be formed by forming a plurality of plates(hereinafter referred to as “inner layers” or “inner layer substrates”)each formed by processing the copper-clad laminate 410, and stacking theplurality of inner layers. The second printed circuit board 342 may beformed through a series of flows including, for example, inner layercircuit printing, inner layer etching, resist peeling, lay-up, stacking,hole-processing, plating, outer layer circuit printing, resist peeling,solder mask printing, and contouring.

Referring to FIGS. 4A and 4B, a structure 420 in which circuit patterns421 and 422 are printed on the surfaces 414 and 415 of the inner layercopper-clad laminate 410 is formed by the inner layer circuit printingaccording to an embodiment. According to an embodiment, through a methodincluding applying a photosensitive dry film to the surfaces 414 and 415of the inner laminate copper-clad laminate 410 with heat and pressure,then irradiating the dry film with light using a master film having apattern thereon, and then developing the dry film (e.g., a photographicprinting method), the circuit patterns (e.g., the portions remaining onthe dry film) 421 and 422 may be printed on the surfaces 414 and 415.According to another embodiment, a circuit pattern corresponding to acircuit may be printed on the surfaces 414 and 415 through a methodusing a silkscreen having a circuit pattern thereon in place of the dryfilm (e.g., a screen-printing method).

Referring to FIGS. 4B and 4C, through the inner layer etching accordingto an embodiment, only the portions 431 and 432 corresponding to theprinted circuit patterns 421 and 422 of the copper foils 412 and 413 areleft, and a remaining portion is removed using a corrosive substance, sothat a structure 430 may be formed. The portions 431 and 432 remainingwithout being corroded by being covered by the circuit patterns 421 and422 may be defined as circuits. Referring to FIGS. 4C and 4D, throughthe resist peeling according to an embodiment, the circuit patterns (orthe etching resists) 421 and 422 are separated, so that an inner layer440 in which circuits 431 and 432 are coupled to the insulating layer411 may be formed. The inner layer 440 may include a first circuit 431and a second circuit 432 respectively disposed on the opposite sides ofthe insulating layer 411. The first circuit 431 or the second circuit432 is shown as a plurality of sectional areas when viewed in crosssection, but may be formed as an integral conductive pattern. Accordingto some embodiments, the first circuit 431 or the second circuit 432 mayinclude a plurality of physically separated patterns.

According to some embodiments, an inner layer including a circuit may beformed by processing a copper-clad laminate having a structure in whicha copper foil is attached to one side of an insulating layer. The innerlayer formed by processing the copper-clad laminate may have a structurein which a circuit is disposed on one side thereof.

Referring to FIGS. 5A and 5B, inner layers 540 and 550 having circuitsformed through the lay-up according to an embodiment may be disposedbetween a first outer layer 511 and a second outer layer 512, which areformed of a copper foil according to a designed stacking structure ofrespective layers in that order. Each inner layer 540 or 550 has astructure in which the circuits 542 and 543 or 552 and 553 are bonded toan insulating layer 541 or 551, and may be formed by processing acopper-clad laminate according to the manufacturing flow described abovewith reference to FIGS. 4A, 4B, 4C, and 4D. When the layers 511, 512,540, 550, 531, 532, and 533 are laid up, the circuits (or wires) 542,543, 552, and 553 located on the inner layers 540 and 550 may be alignedat designed positions. Through the stacking according to an embodiment,when prepregs 531, 532, and 533 having the functions of adhesion andinsulation are disposed between the layers (e.g., the first outer layer511, the second outer layer 512, and the inner layers 540 and 550) andthen high heat and pressure are applied, it is possible to form a firststructure 501 in which the layers 511, 512, 540, 550, 531, 532, and 533are bonded to each other. The prepregs 531, 532, and 533 may be athermosetting resin including an epoxy resin or glass impregnated withan epoxy resin. According to certain embodiments, the first structure501 may be formed to include three or more inner layers without beinglimited to the illustrated example.

According to an embodiment, one inner layer (hereinafter, referred to asa “first inner layer”) 540 includes a first circuit 542 and a secondcircuit 543 respectively disposed on the opposite sides of theinsulating layer 541, and another inner layer (hereinafter, referred toas a “second inner layer”) 550 may include a third circuit 552 and afourth circuit 553 respectively disposed on the opposite sides of theinsulating layer 551. According to some embodiments, at least one of thefirst and second inner layers 540 and 550 may have a structure in whicha circuit is disposed on one side of the insulating layer.

Referring to FIGS. 5B and 5C, in an embodiment, by performinghole-processing (e.g., drilling) in a first structure 501, a secondstructure 502 including a through-hole (or a via) 561 may be formed. Thethrough hole may be defined as a hole perforated in a substrate (e.g.,the first structure 501) including outer layers (e.g., the outer layers511 and 512), prepregs (e.g., the prepregs 531, 532, and 533), and innerlayers (e.g., the inner layers 540 and 550) for the purpose of disposinga connection lead in order to electrically connect conductor layersdisposed in different layers. Depending on the position at which thethrough hole is formed, or on the stacking structure corresponding tothe position, the conductor layers penetrated by the through hole (e.g.,the first outer layer 511 and the second outer layer 512 and one or morecircuits included in the inner layers disposed therebetween) may vary.For example, as illustrated in the drawings, a through hole 561 may beformed to penetrate the first outer layer 511, the first circuit 542 andthe second circuit 543 of the first inner layer 540, the third circuit552 and the fourth layer 553 of the second inner layer 550, and thesecond outer layer 512.

Referring to FIGS. 5C and 5D, in an embodiment, the second structure 502is plated to form a third structure 503 in which the through hole 561 iscoated with a conductive material 563 such as copper. Since the face 562of the through hole 561 does not have an electrical property,electroless copper plating that does not require electricity isprimarily performed using a chemical agent first, and then copper may besecondary plated thereon through electroplating. The plated conductivematerial 563 electrically interconnects conductive portions which areseparated from each other as layers (e.g., the first outer layer 511,the second outer layer 512, and the circuits of the inner layers 540 and550). Depending on the position at which the through hole is formed orthe stacking structure corresponding to the position, the face of thethrough hole may include the inner walls formed in various layers. Forexample, as illustrated in the drawings, the face 562 of the throughhole 561 has inner walls formed in the outer layers 511 and 512, innerwalls formed in the prepregs 531, 532, and 533, inner walls formed bythe insulating layers 541 and 551, an inner wall formed in the firstcircuit 542, an inner wall formed in the second circuit 543, an innerwall formed in the third circuit 552, and an inner wall formed in thefourth circuit 543. These inner walls are coated with the conductivematerial 563, and the outer layers 511 and 512, the first circuit 542,the second circuit 543, the third circuit 552, and the fourth circuit553 may be electrically connected by the conductive material 563.According to some embodiments, a hole partially pitted from the firstouter layer 511 toward the second outer layer 512 or a hole partiallypitted from the second outer layer 512 toward the first outer layer 511is formed, and a conductive material may be plated over the face of thehole.

Referring to FIGS. 5D and 5E, in an embodiment, outer layer circuitprinting for printing a circuit pattern on the surfaces of the firstouter layer 511 and the second outer layer 512 of the third structure503 may be performed by applying the same method as the inner layercircuit printing, and outer layer etching and resist peeling forremoving a part of the first outer layer 511 and a part of the secondouter layer 512 may be performed by applying the same methods as thoseused for the inner layer etching and the resist peeling. In the fourthstructure 504 formed in this manner, portions remaining after partiallyremoving the first outer layer 511 form a first outer layer circuit 571,and portions remaining after partially removing the second outer layer512 form a second outer layer circuit 572. Depending on the position atwhich the through hole is formed, or the stacking structurecorresponding to the position, the conductive layers in which the firstouter layer 571 and the second outer layer 572 are electricallyconnected via the conductive material 563 (e.g., the first outer layer511, the second outer layer 512 and one or more circuits included in theinner layers disposed therebetween) may vary. For example, asillustrated in the drawings, the first outer layer circuit 571 and thesecond outer layer circuit 572 may be electrically connected to thefirst circuit 542 and the second circuit 543 of the first inner layer540 and the third circuit 552 and the fourth circuit 543 of the secondinner layer 550 via the conductive material 563.

Referring to FIGS. 5E and 5F, in an embodiment, by performing soldermask printing on the fourth structure 504, a fifth structure 505 may beformed in which at least a part of the first outer layer circuit 571 orat least a part of the second outer layer circuit 572 is coated withinsulating materials 581 and 582 such as solder mask insulating ink ofepoxy component. The portions covered by the insulating materials 581and 582 in the outer layer circuits 571 and 572 are not exposed to theoutside, and thus oxidation thereof can be prevented. The insulatingmaterials 581 and 582 may also serve to prevent solder bridges frombeing generated during component mounting. According to an embodiment,in solder mask printing, photosensitive ink (e.g., photo S/R) may beapplied to the entire corresponding face through a silkscreen-printingmethod or a spray-coating method, unnecessary portions may be removedthrough exposure and development, and then a remaining portion may becured. According to some embodiments, in the solder mask printing,thermosetting ink may be directly applied to the corresponding areathrough the silkscreen-printing method. The exposed portions (notillustrated) of the first outer layer circuit 571 and the second outerlayer circuit 572 may be used as terminals for soldering connection withother elements. The structure 505 of FIG. 5F is subjected topost-processing such as contouring (e.g., cutting) or surface treatment,and thus the final second printed circuit board (e.g., the secondprinted circuit 342 in FIG. 3) may be formed. The second printed circuitboard according to the structure 505 of FIG. 5F is formed in a structurein which the first outer layer circuit 571 and the second outer layercircuit 572 are electrically connected to the first circuit 541 and thesecond circuit 542 of the first inner layer 540 and the third circuit552 and the fourth circuit 553 of the second inner layer 550 via theconductive material 563, but may be designed to have various otherwiring forms without being limited thereto.

According to certain embodiments, referring to FIG. 3 again, the firstprinted circuit board 341 may also be formed according to the multilayerprinted circuit board manufacturing flow described above with referenceto FIGS. 4A, 4B, 4C, and 4D and FIGS. 5A, 5B, 5C, 5D, 5E, and 5F.

According to some embodiments, the second printed circuit board formedon the basis of the copper-clad laminate may be a single-side printedcircuit board in which a circuit is formed on only one side or adouble-sided printed circuit board in which a circuit is formed on bothsides. The double-sided printed circuit board may include through holesor vias connecting upper and lower circuits.

For example, the single-sided printed circuit board may be formedthrough a series of flows including circuit printing, copper foiletching, resist peeling, solder mask printing, hole-processing, andcontouring on the basis of a copper-clad laminate. Each process has beendescribed in the flow of forming a multilayer printed circuit board, anda detailed description thereof will be omitted.

For example, the double-sided printed circuit board may be formedthrough a series of flows including hole-processing, plating, circuitprinting, copper foil etching, resist peeling, solder mask printing, andcontouring on the basis of a copper-clad laminate. According to someembodiments, the double-sided printed circuit board may be formedthrough a series of flows including hole-processing, plating, circuitprinting, resist peeling, copper foil etching, solder mask printing, andcontouring on the basis of a copper-clad laminate. Each process has beendescribed in the flow of forming a multilayer printed circuit board, anda detailed description thereof will be omitted.

FIG. 6 is a view for explaining contouring of a printed circuit boardaccording to certain embodiments.

Referring to FIG. 6, a printed circuit board 600 may include a firstportion 610 in which areas 601 corresponding to a first printed circuitboard are arranged, and a second portion 620 in which areas 602corresponding to a second printed circuit board are arranged. Theprinted circuit board 600 may also be formed according to, for example,the multilayer printed circuit board manufacturing flow described abovewith reference to FIGS. 4A, 4B, 4C, and 4D and FIGS. 5A, 5B, 5C, 5D, 5E,and 5F.

According to an embodiment, the areas 601 corresponding to the firstprinted circuit board and the areas 602 corresponding to the secondprinted circuit board may be separated from the printed circuit board600 through the contouring. For example, press processing using a moldor a computer numerical control (CNC) type routing equipment may beutilized for the contouring. Further referring to FIG. 3, each of theareas 601 illustrated in FIG. 6 corresponds to the first printed circuitboard 341 of FIG. 3, and each of the areas 602 illustrated in FIG. 6corresponds to the second printed circuit board 342 of FIG. 3. Accordingto an embodiment, due to the size of the original plate on which theprinted circuit board 600 is formed, the second portion 620 maycorrespond to an area in which it is difficult to design an areacorresponding to the first printed circuit board. The areas 602corresponding to the second printed circuit board (e.g., the secondprinted circuit board 342 in FIG. 3) are designed using this second part620, so that costs can be reduced.

According to some embodiments, the second printed circuit board (e.g.,the second printed circuit board 342 in FIG. 3) may be formed on thebasis of another original plate different from the first printed circuitboard (e.g., the first printed circuit board 341 in FIG. 3).

FIG. 7 is an exploded perspective view of printed circuit boardsaccording to an embodiment.

Referring to FIG. 7, in an embodiment, the printed circuit board 700 mayinclude a first printed circuit board 710 and a second printed circuitboard 720, which are coupled to overlap each other. The first printedcircuit board 710 (e.g., the first printed circuit board 341 in FIG. 3)or the second printed circuit board 720 (e.g., the second printedcircuit board 342 in FIG. 3) may also be formed according to themultilayer printed circuit board manufacturing flow described above withreference to FIGS. 4A, 4B, 4C, and 4D and FIGS. 5A, 5B, 5C, 5D, 5E, and5F.

According to an embodiment, the first printed circuit board 710 mayinclude a first area 711, a second area 712, and a third area 713disposed between the first area 711 and the second area 712. The thirdarea 713 may be formed to have a narrower width than the first area 711or the second area 712. For example, the first area 711, the second area712, and the third area 713 are arranged in the y-axis direction, and inthe x-axis direction, the width W3 of the third area 713 may be narrowerthan the width W1 of the first area 711 or the width W2 of the secondarea 712.

According to an embodiment, the second printed circuit board 720 mayinclude a fourth area 714, a fifth area 715, and a sixth area 716disposed between the fourth area 714 and the fifth area 715. The secondprinted circuit board 720 may be coupled to overlap the first printedcircuit board 710 so as to be utilized as a reinforcing member forreinforcing the rigidity of the third area 713 of the first printedcircuit board 710. The first printed circuit board 710 may include aplurality of terminals 701, 702, and 705 disposed, for example, on thefront face 731 thereof facing the rear face (not illustrated) of thesecond printed circuit board 720. The second printed circuit board 720may include a plurality of terminals 703, 704, and 706 disposed, forexample, on the rear face thereof. When the plurality of terminals 701,702, and 705 of the first printed circuit board 710 and the plurality ofterminals 703, 704, and 706 of the second printed circuit board 720 arecoupled through solder, the second printed circuit board 720 may bedisposed to overlap the first printed circuit board 710 and mayreinforce the third area 713. For example, the third area 713 has anarrower width than the first area 711 or the second area 712, while thesecond printed circuit board 720 may reduce an impact or loadtransmitted to the third area 713.

According to an embodiment, the first printed circuit board 710 mayinclude a first electrical terminal 701 disposed in the first area 711and a second electrical terminal 702 disposed in the second area 712.The second printed circuit board 720 may include a third electricalterminal 703 disposed in the fourth area 714 and a fourth electricalterminal 704 disposed in the fifth area 715, and the third terminal 703and the fourth electrical terminal 704 may be electrically connectedthrough a circuit (not illustrated) included in the second printedcircuit board 720. When the first printed circuit board 710 and thesecond printed circuit board 720 are coupled to each other, the firstelectrical terminal 701 may be coupled to the third electrical terminal703 via solder, and the second electrical terminal 702 may be coupled tothe fourth electrical terminal 704 via solder. Thereby, the firstelectrical terminal 701 and the second electrical terminal 702 may beelectrically connected to each other through the second printed circuitboard 720. According to some embodiments, the first printed circuitboard 720 may include a circuit that electrically connects the firstelectrical terminal 701 and the second electrical terminal 702, and thiscircuit may extend to the third area 713.

According to an embodiment, the first printed circuit board 710 mayinclude a first ground terminal 705 disposed in the third area 713, andthe first ground terminal 705 may be electrically connected to a firstground (or a first ground circuit) included in the first printed circuitboard 710 or may be a part of the first ground (or the first groundcircuit). According to an embodiment, the second printed circuit board720 may include a second ground terminal 706 disposed in the sixth area716, and the second ground terminal 706 may be electrically connected toa second ground (or a second ground circuit) included in the secondprinted circuit board 720 or may be a part of the second ground (or thesecond ground circuit). When the first printed circuit board 710 and thesecond printed circuit board 720 are coupled, solder interconnecting thefirst ground terminal 705 and the second ground terminal 706 isdisposed, by which the first ground and the second ground can beelectrically connected to each other.

According to an embodiment, at least some of the first electricalterminal 701, the second electrical terminal 702, the third electricalterminal 703, the fourth electrical terminal 704, the first groundterminal 705, and the second ground terminal 706 may be conductive pads.According to some embodiments, at least some of the first electricalterminal 701, the second electrical terminal 702, the third electricalterminal 703, the fourth electrical terminal 704, the first groundterminal 705, and the second ground terminal 706 may be terminalsutilizing through holes or vias, which are plated with a conductivematerial. In certain embodiments, electrical terminals can be conductivematerial disposed on a surface covering a large enough surface area toform electrical contact by physical placement of an external device.

According to certain embodiments, a side face 723 of the second printedcircuit board 720 may be at least partially surrounded by a conductivematerial, and the conductive material may be utilized for reducing noisegenerated by an electronic device (e.g., the electronic device 100 inFIG. 1 or 2) or electromagnetic interference (EMI). For example, theside face 723 of the second printed circuit board 720 may be plated witha conductive material.

According to some embodiments, the first ground terminal 705 and thesecond ground terminal 706 may be omitted.

According to some embodiments, the first ground terminal 705 may bereplaced by a first metal pad (or a first dummy pad) physicallyseparated from a conductive portion (e.g., circuits) included in thefirst printed circuit board 710. The second ground terminal 706 may bereplaced by a second metal pad (or a second dummy pad) physicallyseparated from a conductive portion (e.g., circuits) included in thesecond printed circuit board 720. According to an embodiment, when thefirst printed circuit board 710 and the second printed circuit board 720are coupled, solder may be disposed to bond the first metal pad and thesecond metal pad to each other. According to certain embodiments, thefirst metal pad and the second metal pad may be coupled to each othervia various other bonding members.

According to certain embodiments, the second metal pad may be expandedto an area in which the third electrical terminal 703 is not disposed inthe fourth area 714 or an area in which the fourth electrical terminal704 is not disposed in the fifth area 715, or other metal pads disposedin these areas may be further formed. The first printed circuit board710 may be formed to have metal pad (s) corresponding to such metal pad(s) of the second printed circuit board 720.

According to some embodiments, the third area 713 and the sixth area 716may be coupled via various bonding members (e.g., polymer or organicadhesive layers) without the first metal pad and the second metal pad.

According to certain embodiments, various other types of first bondingportions may be formed to replace the first metal pad, and various othertypes of second bonds may be formed to replace the second metal pad. Forexample, an optical adhesive member (e.g., a material cured by specifiedlight) or a thermosetting material may be disposed between the firstbonding portion and the second bonding portion. According to certainembodiments, the adhesive member may be designed to be included in thefirst or second bonding portion. According to some embodiments, thefirst bonding portion and the second bonding portion may be coupledthrough bolt fastening.

FIG. 8 is a cross-sectional view illustrating the coupled state of afirst printed circuit board and a second printed circuit board accordingto an embodiment.

Referring to FIG. 8, in an embodiment, a first printed circuit board 810(e.g., the first printed circuit board 341 in FIG. 3 or the firstprinted circuit board 710 in FIG. 7) and a second printed circuit board820 (e.g., the second printed circuit board 342 in FIG. 3 or the secondprinted circuit board 720 in FIG. 7) may be coupled to overlap eachother. The first printed circuit board 810 or the second printed circuitboard 820 may also be formed according to the multilayer printed circuitboard manufacturing flow described above with reference to FIGS. 4A, 4B,4C, and 4D and FIGS. 5A, 5B, 5C, 5D, 5E, and 5F.

According to an embodiment, the first printed circuit board 810 mayinclude a first area 811, a second area 812, and a third area 813disposed between the first area 811 and the second area 812. The secondprinted circuit board 820 may include a fourth area 814, a fifth area815, and a sixth area 816 disposed between the fourth area 814 and thefifth area 815. The fourth area 814 may be disposed to at leastpartially overlap the first area 811, the fifth area 815 may be disposedto at least partially overlap the second area 812, and the sixth area816 may be disposed to at least partially overlap the third area 813.

According to an embodiment, the first printed circuit board 810 mayinclude first electrical terminals 801 (e.g., the first electricalterminal 701 in FIG. 7) disposed in the first area 811, secondelectrical terminals 802 (e.g., the second electrical terminal 702 inFIG. 7) disposed in the second area 812, and first ground terminals 805(e.g., the first ground terminal 705 in FIG. 7) disposed in the thirdarea 813. The second printed circuit board 820 may include thirdelectrical terminals 803 (e.g., the third electrical terminal 703 inFIG. 7) disposed in the fourth area 814, fourth electrical terminals 804(e.g., the fourth electrical terminal 704 in FIG. 7) disposed in thefifth area 815, and second ground terminals 806 (e.g., the second groundterminal 706 in FIG. 7) disposed in the sixth area 816. The firstelectrical terminals 801 may be coupled to the third electricalterminals 803 via solder 841, the second electrical terminals 802 may becoupled to the fourth electrical terminals 804 via solder 842, and thefirst ground terminals 805 may be coupled to the second ground terminals806 via solder 843. According to an embodiment, the third electricalterminals 803 and the fourth electrical terminals 804 may beelectrically connected by a circuit included in the second printedcircuit board 820, whereby the first electrical terminals 801 and thesecond electrical terminals 802 may be electrically connected throughthe second printed circuit board 820. The first ground terminals 805 maybe electrically connected to a first ground included in the firstprinted circuit board 810, and the second ground terminals 806 may beelectrically connected to a second ground included in the second printedcircuit board 820.

The amount of soldering material in solders 841, 842, and 843 or thegaps between the electrical terminals 803, 804, and 806 may an amountlimited to prevent connection to each other (e.g., to form a solderbridge) when the first printed circuit board 810 and the second printedcircuit board 820 are coupled. According to certain embodiments, it isnatural that various other conductive bonding materials may be appliedto replace the solders 841, 842, and 843, in which case the terminals ofthe first printed circuit board 810 and the second printed circuit board820 may also be modified differently.

According to certain embodiments, the thickness T1 of the first printedcircuit board 810 and the thickness T2 of the second printed circuitboard 820 may be the same as or different from each other.

According to certain embodiments, the number of inner layers (e.g.,structure 440 in FIG. 4D) included in the first printed circuit board810 and the number of inner layers included in the second printedcircuit board 820 may be the same as or different from each other.

According to some embodiments, the first ground terminal 805 and thesecond ground terminal 806 may be omitted.

FIG. 9 is a view illustrating an electronic device including overlappingprinted circuit boards according to certain embodiments.

Referring to FIG. 9, in an embodiment, an electronic device 900 (e.g.,the electronic device 100 in FIG. 1) may include a first printed circuitboard 910, and a second printed circuit board 921 and a third printedcircuit board 922, which are coupled to overlap the first printedcircuit board 910. According to an embodiment, the first printed circuitboard 910 may include the first printed circuit board 710 of FIG. 7 orthe first printed circuit board 810 of FIG. 8, and the second and thirdprinted circuit boards 921 and 922 may include the second printedcircuit board 720 of FIG. 7 or the second printed circuit board 820 ofFIG. 8.

According to one embodiment, the first printed circuit board 910 may beintegrally formed with a side bezel structure 950 (e.g., the side bezelstructure 310 in FIG. 3) of the electronic device 900, or may be coupledto a support member 960 (e.g., the first support member 311 in FIG. 3)connected to the side bezel structure 950. The side bezel structure 950may include first to fourth side face member 951 to 954. The first sidemember 951 may be disposed parallel to the second side member 952 in they-axis direction at a distance from the second side member 952. Thethird side members 953 may be disposed parallel to the fourth sidemember 954 in the x-axis direction at a distance from the fourth sidemember 954. According to an embodiment, a connection portion between thefirst side member 951 and the third side member 953, a connectionportion between the first side member 951 and the fourth side member954, a connection portion between the second side member 952 and thethird side member 953, or a connection portion between the second sidemember 952 and the fourth side member 954 may provide a smoothly curvedside face.

According to an embodiment, the first printed circuit board 910 mayinclude an opening 914 that supports the placement of a camera 970(e.g., the second camera device 112 in FIG. 2). The camera 970 is anintegrated component including a lens, an image sensor, and/or an imagesignal processor, and is inserted into the opening 914. The camera 970may include a flexible printed circuit (FPCB) electrically connected tothe first printed circuit board 910. According to an embodiment, thefirst printed circuit board 910 may include a third area 913 (e.g., thethird area 713 in FIG. 7) disposed between the opening 914 in theperipheral areas defining the opening 914 and the first side member 951.According to an embodiment, the first printed circuit board 910 mayinclude a first area 911 (e.g., the first area 711 in FIG. 7) disposedbetween the third area 913 and the third side member 953, and a secondarea 912 (e.g., the second area 712 in FIG. 7) disposed between thethird area 913 and the fourth side member 954. According to anembodiment, the first area 911 and the second area 912 may extend todefine an opening 914. The third area 913 connects the first area 911and the second area 912, and according to an embodiment, the third area913 may have a narrower width than the first area 911 or the second area912 in the y-axis direction (e.g., the direction between the first sidemember 951 and the second side member 952).

According to an embodiment, the first printed circuit board 910 mayinclude a first electrical terminal (e.g., the first electrical terminal701 in FIG. 7) disposed in the first area 911 and a second electricalterminal (e.g., the second electrical terminal 702 in FIG. 7) disposedin the second area 912. The first printed circuit board 910 may includea first ground terminal (e.g., the first ground terminal 705 in FIG. 7)disposed in the third area 913. The second printed circuit board 921 mayinclude, on the rear face thereof, a third electrical terminal (e.g.,the third electrical terminal 703 in FIG. 7) coupled with the firstelectrical terminal, a fourth electrical terminal (e.g., the fourthelectrical terminal 704 in FIG. 7) coupled with the second electricalterminal, and a second ground terminal (e.g., the second ground terminal706 in FIG. 7) coupled with the first ground terminal.

According to an embodiment, the first electrical terminal, the firstground terminal, and the second electrical terminal may be arranged inthe x-axis direction (e.g., the direction between the third side member953 and the fourth side member 954). The second printed circuit board921 may be in a form such that it is extended to overlap the third area913 when connected to the first electrical terminal and the secondelectrical terminal. According to certain embodiments, the firstelectrical terminal or the second electrical terminal may be disposed inthe vicinity of the third area 913 (e.g., within about 20 mm).

According to an embodiment, the first electrical terminal and the secondelectrical terminal may be electrically connected to each other throughthe second printed circuit board 921. According to an embodiment, thethird area 913 may be designed so as to obviate wiring for electricallyconnecting the first electrical terminal and the second electricalterminal, or according to some embodiments, so as to include wiring forconnecting the first electrical terminal and the second electricalterminal.

According to certain embodiments, the first electrical terminal may beelectrically connected to a first component mounted on the first area911, and the second electrical terminal may be electrically connected toa second component mounted on the second area 912.

According to an embodiment, the second printed circuit board 921 iscapable not only of reinforcing the third area 913 of the first printedcircuit board 910, but also of being used as a wiring area forsupporting the first printed circuit board 910 without increasing thewidth of the third area 913 or without designing the third area 913 soas to increase the wiring density.

According to an embodiment, the first printed circuit board 910 mayinclude a seventh area 917 extending from the second area 912 to a spacebetween the battery 940 (e.g., the battery 350 in FIG. 3) and the fourthside member 954, an eighth area 918 disposed on the side of the secondside member 952, and a ninth area 919 between the seventh area 917 andthe eighth area 918. In the x-axis direction, the ninth area 919 (e.g.,the third area 713 in FIG. 7) may have a width narrower than that of theseventh area 917 (e.g., the first area 711 in FIG. 7) or the eighth area918 (e.g., the second area 712 in FIG. 7). According to an embodiment,the third printed circuit board 922 may be coupled to overlap the firstprinted circuit board 910 and may be disposed to overlap the ninth area919. The third printed circuit board 922 is capable not only ofreinforcing the ninth area 919 of the first printed circuit board 910,but also of being used as a wiring area for supporting the first printedcircuit board 910 without increasing the width of the ninth area 919 orwithout designing the ninth area 919 to increase the wiring density.

According to an embodiment, the ninth area 919 may be a portion on whicha motor is mounted. The motor may be for causing the electronic deviceto mechanically oscillate. For example, the motor may be disposedbetween the ninth area 919 and the support member 960.

FIG. 10 is a view illustrating an electronic device includingoverlapping printed circuit boards according to certain embodiments.

Referring to FIG. 10, in an embodiment, an electronic device 1000 (e.g.,the electronic device 100 in FIG. 1) may include a first printed circuitboard 1010, and one or more second printed circuit boards 1021, 1022,and 1023, which are coupled to overlap the first printed circuit board1010. The first printed circuit board 1010 may include, for example, afirst area 1011 (e.g., the first area 711 in FIG. 7), a second area 1012(e.g., the second area 712 in FIG. 7), which is spaced apart from thefirst area 1011 by a distance D1, and a third area 1013 (e.g., the thirdarea 713 in FIG. 7) connecting the first area 1011 and the second area1012.

According to an embodiment, the first printed circuit board 1010 mayinclude the first printed circuit board 710 of FIG. 7 or the firstprinted circuit board 810 of FIG. 8, and the second printed circuitboards 1021, 1022, and 1023 may include the second printed circuit board720 of FIG. 7 or the second printed circuit board 820 of FIG. 8.

According to an embodiment, the first printed circuit board 1010 may beintegrally formed with a side bezel structure 1050 (e.g., the side bezelstructure 310 in FIG. 3) of the electronic device (e.g., the electronicdevice 100 in FIG. 1 or 2), or may be coupled to a support member 1060(e.g., the first support member 311 in FIG. 3) connected to the sidebezel structure 1050. The side bezel structure 1050 may include a firstside member 1051 (e.g., the first side member 951 in FIG. 9), a secondside member 1052 (e.g., the second side member 952 in FIG. 9), a thirdside member 1053 (e.g., the third side member 953 in FIG. 9), and afourth side member 1054 (e.g., the fourth side member 954 in FIG. 9).According to an embodiment, a battery 1040 (e.g., the battery 350 inFIG. 3) may be disposed between the first area 1011 and the second area1012, and between the third area 1013 and the fourth side member 1054.The third area 1013 may have a shape protruding and extending from thefirst area 1011 or the second area 1012 to a space between the battery1040 and the third side member 1053. In a direction oriented from thethird side member 1053 toward the fourth side member 1054 (e.g., thex-axis direction), the third area 1013 may have a width narrower thanthat of the first area 1011 or the second area 1012.

According to an embodiment, the second printed circuit boards 1021,1022, and 1023 may include a printed circuit board 1021 coupled tooverlap the third area 1013, a printed circuit board 1022 coupled tooverlap the first area 1011 and the third area 1013, or a printedcircuit board 1023 coupled to overlap the second area 1012 and the thirdarea 1013. The second printed circuit boards 1021, 1022, and 1023 may becoupled to the first printed circuit board 1010 via solder, so that thesecond printed circuit boards 1021, 1022, and 1023 are able to reinforcethe third area 1013. Since the third area 1013 has a narrower width thanthat of the first area 1011 or the second area 1012, the third area 1013may be vulnerable to breakage due to impact or load. However, the secondprinted circuit boards 1021, 1022, and 1023 are able to suppress theimpact or load from being applied to the third area 1013 and improverigidity. Since the third area 1013 can have a narrower width,substantial rigidity, it is possible to secure a space 1041 required fordisposing the battery 1040 therein. According to certain embodiments,some of the second printed circuit boards 1021, 1022, and 1023 may beomitted.

According to certain embodiments, the third area 1013 of the firstprinted circuit board 1010 may include portions formed like the firstarea 711, the second area 712, and the third area 713 of FIG. 7. Thesecond printed circuit board 1021 may be coupled to the third area 1013of the first printed circuit board 1010, like the second printed circuitboard 720 of FIG. 7.

According to some embodiments, at least one of the second printedcircuit boards 1021, 1022, and 1023 may be disposed between the supportmember 1060 and the first printed circuit board 1010.

For example, electronic components may transmit or receive signals ordata through signal lines included in the first printed circuit board1010. Due to a current flow, an electric field is formed in the signallines, and this electric field causes electromagnetic interference (EMI)that interferes with the normal operation of the electronic componentsby applying noise to a nearby electronic component or signalstransmitted to another nearby signal line. In order to suppress suchelectromagnetic interference, the signal lines may be designed to belocated as far away as possible from other nearby signal lines andelectronic components, or may be designed to further increase the volumethereof. It may difficult to design the third area 1013 to have anexpanded width due to the limited space between the third side member1053 and the battery 1040. Accordingly, in consideration ofelectromagnetic interference, it may be difficult to design the thirdarea 1013 such that the number of signal lines in the third area 1013 isincreased (e.g., the wiring density is increased) or such that thevolume of the signal lines included in the third area 1013 is increased.In order to overcome such design constraints, according to anembodiment, the second printed circuit boards 1021, 1022, and 1023 maybe utilized as signal lines for data transmission/reception.

As another example, current may be set to be equal to or lower than thevalue that can safely flow in the signal lines (e.g., maximum current).The maximum current is a value allowed by the electronic componentsconnected to the signal lines, and the signal lines can be designed toallow this maximum current. For example, when current flows through asignal line, heat may be generated due to the electrical resistance ofthe signal line. The heat raises the temperature of the signal line, andwhen the temperature rises above a certain limit, the signal line may bedamaged (e.g., weakened or broken). As another example, incineration maybe caused in the signal line and in the vicinity of the signal line dueto the heat generated from the signal line. In order to prevent thesignal line from being damaged due to the heat generated when thecurrent flows through the signal line, the signal line may include amaterial having electrical resistance as low as possible, or may bedesigned to have as large a volume as possible. According to anembodiment, a connector (e.g., a USB connector) 1080 may be disposed inthe second area 1012. When current is supplied from the external powersupply through the connector 1080, the current may flow to the firstarea 1011 through the second area 1012 and the third area 1013. It maydifficult to design the third area 1013 to have an expanded width due tothe limited space between the third side member 1053 and the battery1040, whereby it may be difficult to design a signal line included inthe third area 1013 to have an expanded volume. According to anembodiment, in order to overcome such design constraints, according toan embodiment, the second printed circuit boards 1021, 1022, and 1023may be utilized as signal lines for current transmission/reception.

According to an embodiment, second grounds (or ground circuits) includedin the second printed circuit boards 1021, 1022, and 1023 may beelectrically connected to a first ground included in the first printedcircuit board 1010. Since the grounds are expanded by the second printedcircuit boards 1021, 1022, and 1023, performance in electromagneticinterference (EMI) may also be improved.

FIG. 11A is a front view of a second printed circuit board according tocertain embodiments. FIG. 11B is a rear view of the second printedcircuit board of FIG. 11A.

Referring to FIGS. 11A and 11B, a second printed circuit board 1100(e.g., the second printed circuit board 720 in FIG. 7) according to anembodiment may include a fourth area 1114, a fifth area 1115, and asixth area 1116 disposed between the fourth area 1114 and the fifth area1115. According to an embodiment, the sixth area 1116 may extendstraight in a first direction 1121 (e.g., the x-axis direction), thefourth area 1114 may extend in a third direction 1123 perpendicular tothe first direction 1121, and the fifth area 1115 may extend in a fourthdirection 1124 opposite the second direction 1122. According to certainembodiments, the width W4 of the sixth area 1116 extending in the seconddirection 1123 or the third direction 1124 may be the same as ordifferent from the width W5 of fourth area 1114 extending in the firstdirection 1121 or the width W6 of the fifth area 1115 extending in thefirst direction 1121. According to certain embodiments, the width W5 ofthe fourth area 1114 may be the same as or different from the width W6of the fifth area 1115.

According to some embodiments, the fourth area 1114 or the fifth area1115 may be designed to extend at an acute or obtuse angle relative tothe sixth area 1116.

Referring to FIG. 11A, in an embodiment, the second printed circuitboard 1100 may include a plurality of terminals disposed on the rearface 1120 (or the back side). The plurality of terminals of the secondprinted circuit board 1100 may be coupled to a plurality of terminalsformed on the first printed circuit board (e.g., the first printedcircuit board 341 in FIG. 3, the first printed circuit board 910 in FIG.9, or the first printed circuit board 1010 in FIG. 10) via solder,whereby the second printed circuit board may be coupled to overlap thefirst printed circuit board. According to an embodiment, the secondprinted circuit board 1100 may include third electrical terminals 1103(e.g., the third electrical terminals 803 in FIG. 8) disposed in thefourth area 1114, fourth electrical terminals 1104 (e.g., the fourthelectrical terminals 804 in FIG. 8) disposed in the fifth area 1115, andsecond ground terminals 1106 (e.g., the second ground terminals 804 inFIG. 8) disposed in the sixth area 1116.

According to an embodiment, the third electrical terminals 1103 aredisposed in a portion of the fourth area 1114 that protrudes in thesecond direction 1122 with respect to the sixth area 1116, and thefourth electrical terminals 1104 may be disposed in a portion of thefifth area 1115, which protrudes in the third direction 1123 withrespect to the sixth area 1116.

According to an embodiment, as illustrated in the drawing, the thirdelectrical terminals 1103 or the fourth electrical terminals 1104 may beterminals utilizing through holes or vias plated with a conductivematerial. According to some embodiments, the third electrical terminals1103 or the fourth electrical terminals 1104 may be designed asconductive pads.

According to an embodiment, as illustrated in the drawing, the secondground terminals 1106 may be formed as conductive pads. According tosome embodiments, the second ground terminals 1106 may be designed asterminals that utilize through holes or vias plated with a conductivematerial.

According to an embodiment, as illustrated in the drawing, the secondground terminals 1106 may be arranged in a row in the first direction1121. According to some embodiments, the second ground terminals may bearranged in two or more rows, in which case the width W4 of the sixtharea 1116 may be increased. According to some embodiments, when thewidth W4 of the sixth area 1116 is maintained, the size of or spacingbetween the second ground terminals may be reduced so that the secondground terminals may be arranged in two or more rows.

According to an embodiment, the third electrical terminals 1103 and thefourth electrical terminals 1104 may be electrically connected through acircuit included in the second printed circuit board 1100. The secondground terminals 1106 may be electrically connected to a ground (or aground circuit) included in the second printed circuit board 110, or maybe a part of the ground (or the ground circuit).

Referring to FIG. 11B, in an embodiment, the second printed circuitboard 1100 may include circuits 1131 and 1132 disposed on the front face1110 thereof, and these circuits 1131 and 1132 may be utilized asantennas. An antenna may be defined as an element capable of convertingan electromagnetic wave for transmission into a free space wave, orconverting a free space wave for reception into an electromagnetic wave.According to an embodiment, the first printed circuit board (e.g., thefirst printed circuit board 341 in FIG. 3) to which the second printedcircuit board 1100 is overlappingly coupled may include a communicationcircuit (e.g., a communication module). The communication circuit may beelectrically connected to the second printed circuit board 1100. Thecommunication circuit may perform various types of communication usingcircuits 1131 and 1132 of the second printed circuit board 1100.

According to some embodiments, the circuits 1131 and 1132 of the secondprinted circuit board 1100 may be utilized as antenna-matching circuits.For example, the first printed circuit board (e.g., the first printedcircuit board 341 in FIG. 3) to which the second printed circuit board1100 is overlappingly coupled may include a frequency adjustmentcircuit. The frequency adjustment circuit may adjust antenna impedanceusing the circuits 1131 and 1132 of the second printed circuit board1100.

According to certain embodiments, antennas may be designed in variousforms at various locations on the second printed circuit board 1100 onthe basis of the radiation characteristics or impedance thereof.

FIG. 12 is a view illustrating a second printed circuit board accordingto certain embodiments.

Referring to FIG. 12, a second printed circuit board 1200 (e.g., thesecond printed circuit board 720 in FIG. 7) according to an embodimentmay include a fourth area 1214, a fifth area 1215, and a sixth area 1216disposed between the fourth area 1214 and the fifth area 1215. Thesecond printed circuit board 1200 may include a face 1237 facing thefirst printed circuit board when the second printed circuit board 1200is coupled to overlap the first printed circuit board (e.g., the firstprinted circuit board 341 of FIG. 3), and a plurality of terminals 1203,1204, and 1206 may be disposed on the face 1237. The sixth area 1216extends in a first direction 1216 and may include second groundterminals 1206 (e.g., the second ground terminal 706 in FIG. 7). Thefourth area 1214 may include a first portion 1231 extending in the firstdirection 1221 from the sixth area 1216 and a second portion 1232extending in the third direction 1223 perpendicular to the firstdirection 1221 to protrude with respect to the sixth area 1216. Some ofthe third electrical terminals 1203 (e.g., the third electrical terminal703 in FIG. 7) may be disposed in the first portion 1231, and some ofthe third electrical terminals 1203 may be disposed in the secondportion 1232. The fifth area 1215 may be formed symmetrically with thefourth area 1214, and may include fourth electrical terminals 1204(e.g., the fourth electrical terminal 704 in FIG. 7). The thirdelectrical terminals 1203 and the fourth electrical terminals 1204 maybe electrically connected through a circuit included in the secondprinted circuit board 1200, and the second ground terminals 1206 may beelectrically connected to a ground circuit included in the secondprinted circuit board 1200.

According to an embodiment, the fourth area 1214, the fifth area 1215,and the sixth area 1216 may form a space portion 1235, which is recessedin a fourth direction 1224 opposite a third direction 1223. When thesecond printed circuit board 1200 is coupled to overlap the firstprinted circuit board (e.g., the first printed circuit board 341 in FIG.3), at least one component mounted on the first printed circuit boardmay be placed in the space 1235. According to an embodiment, the sideface of the second printed circuit board 1200, which forms the space1235, may be formed as a smoothly curved face 1236.

According to certain embodiments, the shape of the second printedcircuit board and the arrangement structure of the terminals of thesecond printed circuit board may be variously designed according to thecorresponding area of the first printed circuit board.

FIG. 13 is a view illustrating a printed circuit board according tocertain embodiments.

Referring to FIG. 13, in an embodiment, a printed circuit board 1300 mayinclude a fourth printed circuit board 1330 (e.g., the first printedcircuit board 710 in FIG. 7) and a fifth printed circuit board 1340(e.g., the second printed circuit board 720 in FIG. 7), and the fifthprinted circuit board 1340 may be coupled such that a part of the fifthprinted circuit board 1340 overlaps the fourth printed circuit board1330. According to an embodiment, the fourth printed circuit board 1330may include a first area 1311, a second area 1312, and a third area 1313disposed between the first area 1311 and the second area 1312. Accordingto an embodiment, the fifth printed circuit board 1340 may include afourth area 1314, a fifth area 1315, and a sixth area 1316 disposedbetween the fourth area 1314 and the fifth area 1315. The sixth area1316 is separated from the fourth printed circuit board 1330, the fourtharea 1314 extending from a first position of the sixth area 1316 iscoupled to the first area 1311 of the fourth printed circuit board 1330,and the fifth area 1315 extending from a second position of the sixtharea 1316 may be coupled to the second area 1312 of the fourth printedcircuit board 1330. A portion of the fourth area 1314, which overlapsthe fourth printed circuit board 1330, and a portion of the fifth area1315, which overlaps the fourth printed circuit board 1330, may includeat least one terminal coupled to the fourth printed circuit board 1330via a conductive bonding material such as solder.

According to an embodiment, the fifth printed circuit board 1340 coupledto the fourth printed circuit board 1330 may reinforce the fourthprinted circuit board 1330. For example, the third area 1313 may beformed to have a width W7 narrower than that of the first area 1311 orthe second area 1312, and the fifth printed circuit board 1340 may havea resistance structure to bear an impact or load transmitted to thethird area 1313. In addition, the fifth printed circuit board 1340 maybe utilized as a wiring area that supports the fourth printed circuitboard 1330. It is possible to reinforce the third area 1313 and secure awiring area by the fifth printed circuit board 1340 without increasingthe width of the third area 1313 or without designing the third area1310 so as to increase the wiring density.

FIG. 14 is a block diagram of an electronic device 1401 (e.g., theelectronic device 100 in FIG. 1 or 2, or the electronic device 300 inFIG. 3), including overlappingly disposed printed circuit boards, in anetwork environment 1400, according to certain embodiments. Referring toFIG. 14, the electronic device 1401 in the network environment 1400 maycommunicate with an electronic device 1402 via a first network 1498(e.g., a short-range wireless communication network), or may communicatewith an electronic device 1404 or a server 1408 via a second network1499 (e.g., a long-range wireless communication network). According toone embodiment, the electronic device 1401 may communicate with theelectronic device 1404 via the server 1408. According to an embodiment,the electronic device 1401 may include a processor 1420, a memory 1430,an input device 1450, a sound output device 1455, a display device 1460(e.g., the display 101 in FIG. 1 or the display 330 in FIG. 3), an audiomodule 1470 (e.g., the audio module 103, 107 or 114 in FIG. 1 or 2), asensor module 1476 (e.g., the sensor module 104 in FIG. 1 or the sensormodule 119 in FIG. 2), an interface 1477, a haptic module 1479, a cameramodule 1480 (e.g., the first camera device 105, the second camera device112, and/or the flash 113 of FIG. 1 or 2) (e.g., the camera module 970in FIG. 9), a power management module 1488, a battery 1489 (e.g., thebattery 350 in FIG. 3, the battery 940 in FIG. 9, or the battery 1040 inFIG. 10), a communication module 1490, a subscriber identificationmodule 1496, and an antenna module 1497. In some embodiments, amongthese components, at least one component (e.g., the display device 1460or the camera module 1480) may be eliminated from the electronic device1401 or other components may be added to the electronic device 101. Insome embodiments, some of these components may be implemented as asingle integrated circuit. For example, the sensor module 1476 (e.g., afingerprint sensor, an iris sensor, or an illuminance sensor) may beimplemented in the state of being embedded in the display device 1460(e.g., a display).

The processor 1420 may control one or more other components (e.g., ahardware or software component) of the electronic device 1401, which areconnected to the processor 1420, and may perform various data processingor arithmetic operations by executing, for example, software (e.g., aprogram 1440). According to an embodiment, as a part of such dataprocessing or operations, the processor 1420 may load instructions ordata received from another component (e.g., the sensor module 1476 orthe communication module 1490) in volatile memory 1432, and may processinstructions or data stored in the volatile memory 1432 and store theresulting data in nonvolatile memory 1434. According to an embodiment,the processor 1420 may include a main processor 1421 (e.g., a centralprocessing unit or an application processor), and an auxiliary processor1423, which operates independently from or together with the mainprocessor 1421 (e.g., a graphic processing device, an image signalprocessor, a sensor hub processor, or a communication processor).Additionally or alternatively, the auxiliary processor 1423 may use lesspower than the main processor 1421, or may be set to be specific to aspecified function. The auxiliary processor 1423 may be implementedseparately from, or as part of, the main processor 1421.

The auxiliary processor 1423 may control at least some functions orstates associated with at least one of the components of the electronicdevice 1401 (e.g., the display device 1460, the sensor module 1476, orthe communication module 1490), on behalf of the main processor 1421,for example, while the main processor 1421 is in an inactive (e.g.,sleep) state, or together with the main processor 1421 while the mainprocessor 1421 is in an active (e.g., application execution) state.According to one embodiment, the auxiliary processor 1423 (e.g., animage signal processor or a communication processor) may be implementedas a part of other functionally related components (e.g., the cameramodule 1480 or the communication module 1490).

The memory 1430 may store various data to be used by at least onecomponent of the electronic device 1401 (e.g., the processor 1420 or thesensor module 1476). The data may include, for example, input data oroutput data for software (e.g., the program 1440) and instructionsassociated therewith. The memory 1430 may include, for example, volatilememory 1432 or nonvolatile memory 1434.

The program 1440 may be stored in the memory 1430 as software, and mayinclude, for example, an operating system 1442, middleware 1444, orapplication 1446.

The input device 1450 may receive instructions or data for use in acomponent (e.g., the processor 1420) of the electronic device 1401 fromthe outside of the electronic device 1401 (e.g., the user). The inputdevice 1450 may include, for example, a microphone, a mouse, or akeyboard.

The sound output device 1455 may output sound signals to the outside ofthe electronic device 1401. The sound output device 1455 may include,for example, a speaker or a receiver. The speaker may be used forgeneral purposes such as multimedia playback or record playback, and thereceiver may be used for receiving incoming calls. According to anembodiment, the receiver may be implemented separately from or as partof the speaker.

The display device 1460 may provide visual information to the outside(e.g., the user) of the electronic device 1401. The display device 1460may include, for example, a display, a hologram device, or a controlcircuit for controlling a projector and a corresponding device.According to an embodiment, the display device 1460 may include a touchcircuit configured to sense a touch, or a sensor circuit (e.g., apressure sensor) configured to measure the strength of force of thetouch.

The audio module 1470 may convert sound into an electrical signal, orvice versa. According to one embodiment, the audio module 1470 mayacquire sound through the input device 1450 or may output sound throughthe sound output device 1455 or an external electronic device (e.g., theelectronic device 1402 (e.g., a speaker or headphone)) connected withthe electronic device 1401, either directly or in a wireless manner.

The sensor module 1476 may sense the operating conditions (e.g., poweror temperature) of the electronic device 1401 or the externalenvironmental state (e.g., the user state), and may generate anelectrical signal or a data value corresponding to the sensed state.According to an embodiment, the sensor module 1476 may include, forexample, a gesture sensor, a gyro sensor, an atmospheric pressuresensor, a magnetic sensor, an acceleration sensor, a grip sensor, aproximity sensor, a color sensor, an infrared (IR) sensor, a biometricsensor, a temperature sensor, a humidity sensor, or an illuminancesensor.

The interface 1477 may support one or more designated protocols that maybe used by the electronic device 1401 so as to be directly or wirelesslyconnected to an external electronic device (e.g., the electronic device1402). According to one embodiment, the interface 1477 may include, forexample, a high definition multimedia interface (HDMI), a universalserial bus (USB) interface, an SD card interface, or an audio interface.

A connection terminal 1478 may include a connector through which theelectronic device 1401 may be physically connected to an externalelectronic device (e.g., the electronic device 1402). According to anembodiment, the connection terminal 1478 may include, for example, anHDMI connector, a USB connector, an SD card connector, or an audioconnector (e.g., a headphone connector).

The haptic module 1479 may convert an electrical signal into amechanical stimulus (e.g., vibration or motion) or an electricalstimulus that may be perceived by the user through a tactile orkinesthetic sense. According to an embodiment, the haptic module 1479may include, for example, a motor, a piezoelectric element, or anelectrical stimulation device.

The camera module 1480 is a device that is capable of capturing, forexample, a still image and a video image. According to an embodiment,the camera module 1480 may include one or more lenses, image sensors,image signal processors, or flashes.

The power management circuit 1488 may manage the power to be supplied tothe external electronic device 1401. According to an embodiment, thepower management module 1488 may be implemented as at least a part of,for example, a power management integrated circuit (PMIC).

The battery 1489 is capable of supplying power to at least one componentof the electronic device 1401. According to an embodiment, the battery1489 may include, for example, a non-rechargeable primary battery, arechargeable secondary battery, or a fuel cell.

The communication module 1490 may establish a direct (e.g., wired)communication channel or a wireless communication channel between theelectronic device 1401 and an external electronic device (e.g., theelectronic device 1402, the electronic device 1404, or the server 1408),and may support communication via the established communication channel.The communication module 1490 may include one or more communicationprocessors, which are operated independently from a processor 1420(e.g., an application processor) and support direct (e.g., wired)communication or wireless communication. According to an embodiment, thecommunication module 1490 may include a wireless communication module1492 (e.g., a cellular communication module, a short-range wirelesscommunication module, or a global navigation satellite system (GNSS)communication module) or a wired communication module 1494 (e.g., alocal area network (LAN) communication module, or a power linecommunication module). A corresponding one of these communicationmodules may communicate with an external electronic device via a firstnetwork 1498 (e.g., a short-range communication network such asBluetooth, Wi-Fi direct, or infrared data association (IrDA)) or asecond network 1499 (e.g., a cellular network, the Internet, or acomputer network (e.g., a telecommunication network such as a LAN or aWAN)). These various types of communication modules may be integratedinto one component (e.g., a single chip) or may be implemented as aplurality of components (e.g., a plurality of chips) that are separatefrom each other. The wireless communication module 1492 may identify orauthenticate the electronic device 1401 in a communication network suchas the first network 1498 or the second network 1499 using subscriberinformation (e.g., an international mobile subscriber identity (IMSI))stored in a subscriber identification module 1496).

The antenna module 1497 may transmit/receive signals or power to/fromthe outside (e.g., an external electronic device). According to anembodiment, the antenna module 1497 may include one or more antennas,from which at least one antenna suitable for a communication scheme usedin a communication network, such as the first network 1498 or the secondnetwork 1499, may be selected by, for example, the communication module1490. The signals or power may be transmitted or received between thecommunication module 1490 and the external electronic device via theselected at least one antenna.

Among the components described above, at least some components may beconnected to each other via a communication scheme (e.g., a bus, ageneral-purpose input and output (GPIO), a serial peripheral interface(SPI), or a mobile industry processor interface (MIPI)), and mayexchange signals (e.g., commands or data) therebetween.

According to an embodiment, the instructions or data may be transmittedor received between the electronic device 1401 and the externalelectronic device 1404 via the server 1408 connected to the secondnetwork 1499. Each of the electronic devices 1402 and 1404 may be of atype that is the same as or different from that of the electronic device1401. According to an embodiment, all or some of the operations executedon the electronic device 1401 may be executed on one or more of theexternal electronic devices 1402, 1404, and 1408. For example, when theelectronic device 1401 is to perform a function or serviceautomatically, or in response to a request from a user or anotherdevice, the electronic device 1401 may request that one or more externalelectronic devices perform at least a part of the function or theservice, in place of or in addition to performing the function orservice by itself. The one or more external electronic devices thatreceive the request may execute at least a portion of the requestedfunction or service, or an additional function or service associatedwith the request, and may deliver the result of the execution to theelectronic device 1401. The electronic device 1401 may process theresult as it is or additionally so as to provide at least a portion ofthe response to the request. For this purpose, for example, cloudcomputing technology, distributed computing technology, or client-servercomputing technology may be used.

According to one embodiment, the electronic device 1401 may include aprinted circuit board (e.g., the printed circuit board 340 in FIG. 3),on which at least some of a processor 1420, a memory 1430, an inputdevice 1450, a sound output device 1455, a display device 1460, an audiomodule 1470, a sensor module 1476, an interface 1477, a haptic module1479, a camera module 1480, a power management module 1488, a battery1489, a communication module 1490, a subscriber identification module1496, and an antenna module 340 are mounted. According to an embodiment,the printed circuit board may include a first printed circuit board (thefirst printed circuit board 341 in FIG. 3) and at least one secondprinted circuit board (the second printed circuit board 342 in FIG. 3)disposed to overlap the first printed circuit board. The first printedcircuit board or the second printed circuit board may also be formedaccording to the multilayer printed circuit board manufacturing flowdescribed above with reference to FIGS. 4A, 4B, 4C, and 4D and FIGS. 5A,5B, 5C, 5D, 5E, and 5F. According to an embodiment, the second printedcircuit board is capable not only of reinforcing the first printedcircuit board, but also of being utilized as a wiring area.

The term “module” used herein may include a unit implemented withhardware, software, or firmware, and may be used interchangeably with,for example, the terms of “logic,” “logic block,” “component, “circuit,”or the like. The module may be an integrally constructed component or aminimum unit or a part of the component, which performs one or morefunctions. For example, according to an embodiment, the module may beimplemented in the form of an application-specific integrated circuit(ASIC).

Certain embodiments disclosed herein may be implemented by software(e.g., the program 1440) including one or more instructions stored in astorage medium (e.g., internal memory 1436 or external memory 1438)readable by a machine (e.g., the electronic device 1401). For example, aprocessor (e.g., the processor 1420) of a device (e.g., the electronicdevice 1401) may call and execute at least one of the stored one or moreinstructions from a storage medium. This enables the device to beoperated to perform at least one function in accordance with the atleast one called instruction. The one or more instructions may includecode generated by a compiler or code capable of being executed by aninterpreter. The machine-readable storage medium may be provided in theform of a non-transitory storage medium. Here, the term “non-transitory”merely means that the storage medium is a tangible device and does notcontain a signal (e.g., electromagnetic waves), and this term is notintended to distinguish between the case where data is permanentlystored on the storage medium and the case where data is temporarilystored thereon.

According to one embodiment, a method according to certain embodimentsdisclosed herein may be provided in the manner of being included in acomputer program product. A computer program product may be tradedbetween a seller and a purchaser as a commodity. The computer programproduct may be distributed in the form of a machine-readable storagemedium (e.g., a compact disc read only memory (CD-ROM)), or may bedistributed through an application store (e.g., Play Store™), directlybetween two user devices (e.g., smart phones), or online (e.g.,downloaded or uploaded). In the case of on-line distribution, at least apart of the computer program product may be temporarily stored in ortemporarily produced from a machine-readable storage medium such as amanufacturer's server, a server of an application store, or a memory ofa relay server.

According to certain embodiments, among the above-described components,each component (e.g., a module or a program) may include one or moreentities. According to certain embodiments, among the components, one ormore components or operations may be omitted, or one or more othercomponents or operations may be added. Alternatively or additionally, aplurality of components (e.g., modules or programs) may be integratedinto one component. In such a case, the integrated component may performone or more functions of each of the plurality of components in a mannerthe same as or similar to performance thereof by the corresponding oneof the plurality of components prior to the integration. According tocertain embodiments, operations performed by a module, a program, orother components may be performed sequentially, in parallel,repetitively, or heuristically, one or more of the operations may beperformed in a different order or omitted, or one or more otheroperations may be added thereto.

According to an embodiment of the disclosure, an electronic device(e.g., the electronic device 100 in FIG. 1 or 2) may include a firstprinted circuit board (e.g., the first circuit board 710 in FIG. 7)including a first electrical terminal 701 exposed on one face of a firstarea (e.g., the first area 711 in FIG. 7), a second electrical terminal702 exposed on one face of a second area (e.g., the second area 712 inFIG. 7) and not electrically connected to the first electrical terminal701, and a first ground terminal 705 exposed on one face of a third area(e.g., the third area 713 in FIG. 7) formed between the first area 711and the second area 712 to have a width narrower than that of the firstarea 711 or the second area 712. The electronic device 100 may include asecond printed circuit board (e.g., the second circuit board 720 in FIG.7) including a third terminal 703 exposed on one face of a fourth area(e.g., the fourth area 714 in FIG. 7), a fourth electrical terminal 704exposed on one face of a fifth area (e.g., the fifth area 715 in FIG. 7)and electrically connected to the third electrical terminal 703, and asecond ground terminal 706 exposed on one face of a sixth area (e.g.,the sixth area 716 in FIG. 7) located between the fourth area 714 andthe fifth area 715. The second printed circuit board 720 may be disposedon the first printed circuit board 710 to overlap the third area 713,the first electrical terminal 701 and the third electrical terminal 703may be electrically coupled to each other, the second electricalterminal 702 and the fourth electrical terminal 704 may be electricallycoupled to each other, and the first ground terminal 705 and the secondground terminal 706 may be electrically coupled to each other.

According to an embodiment of the disclosure, the first printed circuitboard 710 or the second printed circuit board 720 may be a printedcircuit board formed using a copper-clad laminate (CCL) (e.g., FR-4)including an insulating layer in which woven glass fiber impregnatedwith an epoxy resin is stacked in multiple layers and copper bonded tothe insulating layer.

According to an embodiment of the disclosure, the first printed circuitboard 710 or the second printed circuit board 720 may be a printedcircuit board formed using a copper-clad laminate (e.g., CEM-3)including a center base material made of non-woven glass fiberimpregnated with an epoxy resin, outer base materials made of wovenglass fiber impregnated with an epoxy resin, and copper foils bonded tothe outer base materials.

According to an embodiment of the disclosure, the second printed circuitboard may include a multilayer printed circuit board.

According to an embodiment of the disclosure, the second printed circuitboard may include a multilayer printed circuit board including innerlayers formed on the basis of the copper-clad laminate, and the numberof inner layers may be equal to that in the first printed circuit board.

According to an embodiment of the disclosure, the second printed circuitboard may include a multilayer printed circuit board including innerlayers formed on the basis of the copper-clad laminate, and the numberof inner layers may be different from that in the first printed circuitboard.

According to an embodiment of the disclosure, the second printed circuitboard may include a double-sided printed circuit board.

According to an embodiment of the disclosure, the second printed circuitboard may have a thickness different from that of the first printedcircuit board.

According to an embodiment of the disclosure, at least a portion of aside face 723 of the second printed circuit board (e.g., the secondprinted circuit board 720 in FIG. 7) may be surrounded by a conductivematerial.

According to an embodiment of the disclosure, the third area (e.g., thethird area 913 in FIG. 9) may be adjacent to an opening 914 formed inthe first printed circuit board 910.

According to an embodiment of the disclosure, the third area (e.g., thethird area 913 in FIG. 9) may be adjacent to a camera module 970included in the electronic device.

According to an embodiment of the disclosure, the electronic device mayfurther include a battery (e.g., the battery 1040 in FIG. 10), and thethird area (e.g., the third area 1013 in FIG. 10) may be adjacent to thebattery 1040.

According to an embodiment of the disclosure, the electronic device mayinclude a motor mounted on the third area (e.g., the ninth area 919 inFIG. 9).

According to an embodiment of the disclosure, the electronic device mayfurther include a solder (e.g., the solder 841, 842, or 843 in FIG. 8)disposed between the first electrical terminal and the third electricalterminal, between the second electrical terminal and the fourthelectrical terminal, or between the first ground terminal and the secondground terminal.

According to an embodiment of the disclosure, at least one of the thirdelectrical terminal, the fourth electrical terminal, and the secondground terminal may include a via.

According to an embodiment of the disclosure, the second printed circuitboard may include an antenna (e.g., the antennas 1131 and 1132 in FIG.11B) disposed on the face facing away from the face that faces the firstprinted circuit board.

According to an embodiment of the disclosure, the electronic device mayfurther include a communication circuit mounted on the first printedcircuit board, and the communication circuit may perform communicationusing the antenna.

According to an embodiment of the disclosure, the second printed circuitboard may be electrically connected to a frequency adjustment circuitmounted on the first printed circuit board.

According to an embodiment of the disclosure, at least a part of thecurrent provided from an external power source connected to theelectronic device may flow from the first area to the second areathrough the second printed circuit board.

According to certain embodiment of the disclosure, an electronic device(e.g., the electronic device 100 in FIG. 1 or 2) may include a firstprinted circuit board (e.g., the first circuit board 710 in FIG. 7)including a first electrical terminal 701 exposed on one face of a firstarea (e.g., the first area 711 in FIG. 7), a second electrical terminal702 exposed on one face of a second area (e.g., the second area 712 inFIG. 7) and not electrically connected to the first electrical terminal701, and a first metal pad formed on one face of a third area (e.g., thethird area 713 in FIG. 7) formed between the first area 711 and thesecond area 712 to have a width narrower than that of the first area 711or the second area 712. The electronic device 100 may include a secondprinted circuit board (e.g., the second circuit board 720 in FIG. 7)including a third terminal 703 exposed on one face of a fourth area(e.g., the fourth area 714 in FIG. 7), a fourth electrical terminal 704exposed on one face of a fifth area (e.g., the fifth area 715 in FIG. 7)and electrically connected to the third electrical terminal 703, and asecond metal pad formed on one face of a sixth area (e.g., the sixtharea 716 in FIG. 7) located between the fourth area 714 and the fiftharea 715 to have a width narrower than that of the first area 711 or thesecond area 712. The second printed circuit board 720 may be disposed onthe first printed circuit board 710 to overlap the third area 713, thefirst electrical terminal 701 and the third electrical terminal 703 maybe electrically coupled to each other, the second electrical terminal702 and the fourth electrical terminal 704 may be electrically coupledto each other, and the first metal pad and the second metal pad may beelectrically coupled to each other.

The disclosure has been described above in connection with the exemplaryembodiments thereof. It will be understood by those skilled in the artto which the disclosure belongs that the disclosure may be implementedin modified forms without departing from the essential characteristicsof the disclosure. Therefore, the embodiments disclosed herein should beconsidered from an illustrative point of view, rather than a limitativepoint of view. The scope of the disclosure is found not in the abovedescription but in the accompanying claims, and all differences fallingwithin the scope equivalent to the claims should be construed as beingincluded in the disclosure.

What is claimed is:
 1. A mobile device comprising: a display facing afirst direction; a housing including a portion forming at least a rearsurface of the mobile device facing a second direction opposite to thefirst direction; a first printed circuit board (PCB) disposed in thehousing, the first PCB having a first surface facing the seconddirection and including a plurality of first terminals exposed on thefirst surface; and a second PCB disposed on the first surface of thefirst PCB, wherein the second PCB includes: a plurality of secondterminals disposed over a side of the second PCB facing the firstsurface of the first PCB, the plurality of second terminals beingcoupled to the plurality of first terminals via a plurality of solders,and at least two antennas configured to radiate wireless signals in thesecond direction in response to electrical signals received from acommunication circuit via the solders provided between the plurality offirst terminals and the plurality of second terminals, and wherein thecommunication circuit is mounted on a second surface of the first PCB,the second surface being opposite to the first surface of the first PCB,and wherein the first PCB or the second PCB is a PCB formed using acopper-clad laminate (CCL) including an insulating layer comprises wovenglass fiber impregnated with an epoxy resin stacked in multiple layersand copper, the copper bonded to the insulating layer.
 2. A mobiledevice comprising: a housing; a first printed circuit board (PCB)disposed in the housing, the first PCB having a first surface facing afirst direction and including a plurality of first terminals exposed onthe first surface; a second PCB disposed on the first surface of thefirst PCB, wherein the second PCB includes: a plurality of secondterminals disposed over a side of the second PCB facing the firstsurface of the first PCB, the plurality of second terminals beingcoupled to the plurality of first terminals via a plurality of solders;and at least two antennas configured to radiate wireless signals in thefirst direction in response to electrical signals received from acommunication circuit via the solders provided between the plurality offirst terminals and the plurality of second terminals, and wherein thecommunication circuit is mounted on a second surface of the first PCB,the second surface being opposite to the first surface of the first PCB,and wherein the first PCB or the second PCB is a PCB formed using acopper-clad laminate (CCL) including an insulating layer comprises wovenglass fiber impregnated with an epoxy resin stacked in multiple layersand copper, the copper bonded to the insulating layer.
 3. The mobiledevice of claim 1, wherein the second PCB includes a plurality oflayers.
 4. The mobile device of claim 3, wherein the plurality of layersof the second PCB includes inner layers formed based on a copper-cladlaminate, and wherein a number of the inner layers is different from anumber of inner layers in the first PCB.
 5. The mobile device of claim1, wherein the second PCB has a thickness different from a thickness ofthe first PCB.
 6. The mobile device of claim 1, further comprising: atleast one processor electrically connected to the communication circuit.7. The mobile device of claim 1, further comprising: a frequencyadjustment circuit configured to adjust an impedance of the at least twoantennas, wherein the frequency adjustment circuit is mounted on thefirst PCB.
 8. The mobile device of claim 1, wherein the rear surface ofthe mobile device is formed of, at least one of coated or colored glass,ceramic, or a polymer.
 9. The mobile device of claim 1, wherein thesecond PCB further comprises a ground terminal electrically connected toa ground of the first PCB.
 10. The mobile device of claim 1, wherein thefirst PCB includes a first set of insulating layers having a firstpermittivity and the second PCB includes a second set of insulatinglayers having a second permittivity lower than the first permittivity.11. A mobile device comprising: a housing; a first printed circuit board(PCB) disposed in the housing, the first PCB having a first surfacefacing a first direction and including a plurality of first terminalsexposed on the first surface; a second PCB disposed on the first surfaceof the first PCB, wherein the second PCB includes: a plurality of secondterminals disposed over a side of the second PCB facing the firstsurface of the first PCB, the plurality of second terminals beingcoupled to the plurality of first terminals via a plurality of solders;and at least two antennas configured to radiate wireless signals in thefirst direction in response to electrical signals received from acommunication circuit via the solders provided between the plurality offirst terminals and the plurality of second terminals, and wherein thecommunication circuit is mounted on a second surface of the first PCB,the second surface being opposite to the first surface of the first PCB.12. The mobile device of claim 11, further comprising: a displaydisposed in the housing.
 13. The mobile device of claim 12, wherein thedisplay faces a second direction opposite the first direction.
 14. Themobile device of claim 11, wherein the at least two antennas aredisposed on a side of the second PCB facing a second direction oppositethe first direction.
 15. The mobile device of claim 11, wherein thesecond PCB includes a plurality of layers.
 16. The mobile device ofclaim 15, wherein the plurality of layers of the second PCB includesinner layers formed based on a copper-clad laminate, and wherein anumber of the inner layers is different from a number of inner layers inthe first PCB.
 17. The mobile device of claim 11, wherein the second PCBhas a thickness different from a thickness of the first PCB.
 18. Themobile device of claim 11, further comprising: at least one processorelectrically connected to the communication circuit.
 19. The mobiledevice of claim 11, further comprising: a frequency adjustment circuitconfigured to adjust an impedance of the at least two antennas, whereinthe frequency adjustment circuit is mounted on the first PCB.
 20. Themobile device of claim 11, wherein the first PCB includes a first set ofinsulating layers having a first permittivity and the second PCBincludes a second set of insulating layers having a second permittivitylower than the first permittivity.